• Title/Summary/Keyword: Chung-pi

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The Study on the Reactivity of Dioxygen Bridged Palladium Complexes Having ${\pi}$-Allyl Ligands (${\pi}$-알릴리간드를 갖는 산소가교 팔라듐착화합물의 반응성에 관한 연구)

  • Pyeong Jin Chung
    • Journal of the Korean Chemical Society
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    • v.30 no.6
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    • pp.516-520
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    • 1986
  • This study is related to reactivity of dioxygen bridged palladium complexes having ${\pi}$-allyl ligands. In this case, new dioxygen bridged palladium complexes were prepared using superoxide ion$(O_2^-)$ as an oxygen source. Reactions of the dioxygen palladium complexes prepared in the study were examined in order to clarify the nature of the coordinated dioxygen. Treatments of a solution of the dioxygen bridged palladium complexes in benzene by water, methanol and acetic acid gave hydrogen peroxide $(H_2O_2)$ as hydroxy-, methoxy-, and acetoxybridged palladium complexes, respectively. The dioxygen bridged palladium complexes reacted also with substitution phenols of salicylaldehyde, 8-hydroxyquinoline and active methylenes of acetylacetone, dimethyl malonate to afford mononuclear complexes of palladium and hydrogen peroxide. The results suggest that dioxygen is coordinated as peroxo $(O_2^{2-})$ in the complexes and behaves as a strong base.

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The Effect of Silicone Toothbrush on Plaque Control and Gingival Inflammation. A Comparative Clinical Study (치태제거 및 치은염증에 대한 실리콘 칫솔의 효과)

  • Chung, Yeh-Jin;;Suh, Jong-Jin;Cho, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.30 no.4
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    • pp.911-923
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    • 2000
  • A comparative clinical study on the ordinary toothbrush($Buttler^{(R)}$, America) and the silicone toothbrush($Jefe^{(R)}$, Korea) was performed. The volunteers who took part in this study were students of Dental college of Yonsei University and patients attending Dental Hospital of Yonsei University. They were classified into two group, control and experimental group. Control group brushed with nylon toothbrush and experimental group did with silicone toothbrush under the researcher's guidances. Volunteers were examined on Plaque Index(PI), Gingival Index(GI), Probing Depth(PD), Bleeding on Probing(BP) and Recession(R) at base line, 1st. week, 2nd. week and 4th. week. According to the results, both group have the tendency of improvement in the degrees of GI, PI and the improvement degree of GI of both group has the significant differences from base line statistically, and there are not statistically significant differences between the silicone and nylon group in respect of PI, GI values. So based on the present study, it could be carefully ascertained that the silicone toothbrush has similar effect with nylon toothbrush in respect of PI and GI. If it is sure that the silicone toothbrush is seldom abrasive and possibly enough to massage the gingiva, this new brush is worth to be recommended by the dentists.

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Comparison of peri-implant marginal bone level changes between tapered and straight implant designs: 5-year follow-up results

  • Park, Han;Moon, Ik-Sang;Chung, Chooryung;Shin, Su-Jung;Huh, Jong-Ki;Yun, Jeong-Ho;Lee, Dong-Won
    • Journal of Periodontal and Implant Science
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    • v.51 no.6
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    • pp.422-432
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    • 2021
  • Purpose: The aim of this study was to compare straight and tapered implant designs in terms of marginal bone loss, the modified plaque index (mPI), and the modified bleeding index (mBI) for 5 years after functional loading. Methods: Twelve patients were recruited. Two types of implants were placed adjacent to each other: 1 straight implant and 1 tapered implant. Marginal bone loss, mPI, and mBI were measured every year for 5 years after loading. Results: The straight implants showed 0.2±0.4 mm of marginal bone loss at 5 years after loading, while the tapered implants showed 0.2±0.3 mm of marginal bone loss; this difference was not statistically significant (P=0.833). Our analysis also showed no statistically significant differences in mPI (straight implants: 0.3±0.3 vs. tapered implants: 0.2±0.3; P=0.414) or in mBI (straight implants: 0.3±0.4 vs. tapered implants: 0.2±0.3; P=0.317) at 5 years after prosthesis delivery. Conclusions: Straight and tapered implants showed no significant differences with respect to marginal bone loss, mPI, and mBI for 5 years after loading.

Construction and basic performance test of an ICT-based irrigation monitoring system for rice cultivation in UAE desert soil

  • Mohammod, Ali;Md Nasim, Reza;Shafik, Kiraga;Md Nafiul, Islam;Milon, Chowdhury;Jae-Hyeok, Jeong;Sun-Ok, Chung
    • Korean Journal of Agricultural Science
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    • v.48 no.4
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    • pp.703-718
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    • 2021
  • An irrigation monitoring system is an efficient approach to save water and to provide effective irrigation scheduling for rice cultivation in desert soils. This research aimed to design, fabricate, and evaluate the basic performance of an irrigation monitoring system based on information and communication technology (ICT) for rice cultivation under drip and micro-sprinkler irrigation in desert soils using a Raspberry Pi. A data acquisition system was installed and tested inside a rice cultivating net house at the United Arab Emirates University, Al-Foah, Al-Ain. The Raspberry Pi operating system was used to control the irrigation and to monitor the soil water content, ambient temperature, humidity, and light intensity inside the net house. Soil water content sensors were placed in the desert soil at depths of 10, 20, 30, 40, and 50 cm. A sensor-based automatic irrigation logic circuit was used to control the actuators and to manage the crop irrigation operations depending on the soil water content requirements. A developed webserver was used to store the sensor data and update the actuator status by communicating via the Pi-embedded Wi-Fi network. The maximum and minimum average soil water contents, ambient temperatures, humidity levels, and light intensity values were monitored as 33.91 ± 2 to 26.95 ± 1%, 45 ± 3 to 24 ± 3℃, 58 ± 2 to 50 ± 4%, and 7160-90 lx, respectively, during the experimental period. The ICT-based monitoring system ensured precise irrigation scheduling and better performance to provide an adequate water supply and information about the ambient environment.

Effectiveness of comprehensive traditional Korean Medicine treatment on quality of life, anorexia and cachexia of cancer patients : Retrospective chart review (암 환자의 삶의 질, 식욕 부진과 악액질에 대한 복합 한의 치료 프로그램의 효과: 후향적 차트 리뷰)

  • Han, Wonju;Lee, Eunji;Han, Gajin;Yoon, Sang-hoon;Han, Gajin;Leem, Jungtae
    • The Journal of Korean Medicine
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    • v.40 no.2
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    • pp.119-132
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    • 2019
  • Purpose: This study was conducted to collect and analyze real world data to evaluate the effectiveness and safety of comprehensive traditional Korean Medicine treatment on quality of life, anorexia and cachexia of cancer patients. Methods: We analyzed medical records of 62 cancer patients admitted to O-I Dang Korean Medicine Hospital from February 2018 to February 2019. The primary outcome was a change score in the Anorexia/Cachexia Subscale of Functional Assessment of Anorexia/Cachexia Therapy (FAACT). The secondary outcomes were Functional Assessment of Cancer Therapy-General (FACT-G), Trial Outcome Index(TOI) of FAACT, 11 point Pain Intensity Numeric Rating Score (11 PI-NRS) and Patient Global Impression of Change (PGIC) and adverse event. Results: Cachexia and quality of life in cancer patients assessed by FAACT, increased by $5.59{\pm}14.83$ (p=0.004) after treatment. PI-NRS was reduced by $2.10{\pm}1.81$ (p<0.001) and TOI and FACT-G total scores were increased by $5.17{\pm}11.70$ (p=0.001) and $3.59{\pm}10.94$ (p=0.012), respectively. These results were also clinically meaningful assessed via minimal clinically important difference (MCID). There was no severe adverse event. Conclusion: These findings suggest that comprehensive traditional Korean Medicine treatment might be effective and safe strategy for improving quality of life, anorexia, cachexia and pain of cancer patients. Further advanced studies with controlled group and more participants with rigorous design are needed to ensure these findings.

Analysis and Design of Permanent Magnet Motor by the Improved Permeance Method (개선된 퍼미언스법에 의한 영구자석 회전기의 해석 및 설계)

  • Chung, Tae-Kyung;Oh, Seung-Suk
    • Proceedings of the KIEE Conference
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    • 1998.07a
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    • pp.175-178
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    • 1998
  • To analyze and design a motor magnetic permeance method and numerical methods such as F.E.M. are used. In this thesis, DC motor is analyzed and designed by the permeance method. Modified Carter coefficient and leakage permeance are presented. A magnetic flux path can be approximated properly by using a equivalent ${\pi}$ network representation adding the leakage coefficient. Finally, effective and easy-to-use program is realized. Experimental analysis and design with an actual motor proves that this program produces reliable results. There are many experimental coefficients in this algorithm and it makes some design errors. Using of this program, an motor engineer can obtain satisfactory characteristic and design value by inputting initial data at once.

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Location Based Personalized Service Platform (위치기반 개인화 서비스 플랫폼)

  • Je, Hyoungyu;Kim, Jiho;Kim, Hyung-Guk;Lee, Sangdo;Song, Ohyoung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2012.11a
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    • pp.1227-1230
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    • 2012
  • 본 논문에서는 IEEE 802.15.4(ZigBee, 지그비)통신기술과 채널 선택(Channel selection)기술을 활용하여 객체가 소지한 능동형 태그의 주기적 비컨신호로 위치를 인식, 추적하여 서버에게 트래킹 정보를 제공해주는 시스템으로써 위치기반 개인화 플랫폼을 구현하였고 효율적인 위치 인식 플랫폼을 위한 코디네이터의 위치 선정에 대한 성능을 평가하였다.

EPIDEMIOLOGICAL EVALUATION OF PERIODONTAL STATUS IN KOREAN ADULTS (한국인의 치주조직상태에 관한 역학조사)

  • Han, Kyung-Yoon;Park, Jun-Bong;Chung, Jin-Hyung;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
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    • v.24 no.3
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    • pp.458-471
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    • 1994
  • To evaluate the periodontal status of Korean adults, 3,988 adults(20-69 years old) who lived in Kwangju, Chonnam, Taegu, and Kyungbuk districts were periodontally examined by plaque index(PI), calculus index(CI), gingival index(GI), periodontal disease index (PDI), and papillary bleeding index(PBI). The periodontal examination charts were grouped according to age and sex. And subsequently 200 periodontal examination charts in each age group were randomly selected according to sex. The differences of the indices among age groups and those between male and female in each age group were statistically analyzed by Chi-Square test. In PI, CI, GI, PDI, and PBI, there was no statistical significance in the difference between male and female in each age group(p>0.05). In male, PI of 60s age group($1.44{\pm}0.68$) was significantly higher than that of any age group(p<0.05), and in female PI of 20s age group($0.86{\pm}0.39$) was significantly lower than that of any other age group(p<0.05). CI of 60s age group in both male($1.67{\pm}0.70$) and female($1.63{\pm}0.91$) was significantly higher than that of any age group(p<0.05). GI of 20s age group in both male($0.85{\pm}0.66$) and female($0.67{\pm}0.60$) was significantly lower and GI of 60s age group in both male($1.37{\pm}0.60$) and female($1.44{\pm}0.84$) was higher than that of any age group(p<0.05). PDI in male was the lowest in 20s age group($0.70{\pm}0.73$), and was the highest in 60s age group($4.93{\pm}1.96$) (p<0.05). In female PDI of 20s age group($0.71{\pm}0.74$) was significantly lower than that of any age group(p<0.05). In male PBI of 20s age group($0.38{\pm}0.31$) was significantly lower than that of any age group(p<0.001). PBI in female was the lowest in 20s age group($0.35{\pm}0.30$) (p<0.001), and was the highest in 60s age group($1.09{\pm}0.76$) (p<0.05). The data insist that all the young populations of 20s age group should be interested in routine check for early diagnosis and prevention of periodontal disease, and a special education program of periodontal health care for young generation must be prepared, and the periodic recall check system for periodontal examination of middle age group must be supported by government.

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Molecular Orientation of Evaporated Pentacene Film on Polyimide Alignment Layer (폴리이미드 배향막에 증착된 Pentacene 분자의 배향 연구)

  • Kim Beom-Kyung;Kim Do-Hoi;Chung Jae-Sun;Kim Young-Ju;Seo In-Seon;Kwon Soon-Ki;Song Ki-Gook
    • Polymer(Korea)
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    • v.30 no.4
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    • pp.362-366
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    • 2006
  • It was found by polarized FTIR spectroscopic studies that pentacene molecules are arranged with their molecular axes perpendicular to the substrate surface when pentacene films are deposited on a polyimide alignment layer. The ring plane in a pentacene molecule is arranged parallel to the rubbing direction of the polyimide alignment film while no specific arrangement of vertically deposited pentacene molecules was found for the film without rubbing. The pentacene band at $1296cm^{-1}$ which has a transition dipole moment parallel to the ring plane is much stronger in a polarized IR spectrum of parallel to the rubbing direction, whereas the band at $908cm^{-1}$ whose transition dipole align normal to the ring plane shows much stronger intensity in a spectrum of perpendicular to the rubbing direction. These findings indicate that orientation of polyimide chains affects the arrangement of pentacene molecules when they are deposited on a polyimide alignment film.

Stereo Vision based on Planar Algebraic Curves (평면대수곡선을 기반으로 한 스테레오 비젼)

  • Ahn, Min-Ho;Lee, Chung-Nim
    • Journal of KIISE:Software and Applications
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    • v.27 no.1
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    • pp.50-61
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    • 2000
  • Recently the stereo vision based on conics has received much attention by many authors. Conics have many features such as their matrix expression, efficient correspondence checking, abundance of conical shapes in real world. Extensions to higher algebraic curves met with limited success. Although irreducible algebraic curves are rather rare in the real world, lines and conics are abundant whose products provide good examples of higher algebraic curves. We consider plane algebraic curves of an arbitrary degree $n{\geq}2$ with a fully calibrated stereo system. We present closed form solutions to both correspondence and reconstruction problems. Let $f_1,\;f_2,\;{\pi}$ be image curves and plane and $VC_P(g)$ the cone with generator (plane) curve g and vertex P. Then the relation $VC_{O1}(f_1)\;=\;VC_{O1}(VC_{O2}(f_2)\;∩\;{\pi})$ gives polynomial equations in the coefficient $d_1,\;d_2,\;d_3$ of the plane ${\pi}$. After some manipulations, we get an extremely simple polynomial equation in a single variable whose unique real positive root plays the key role. It is then followed by evaluating $O(n^2)$ polynomials of a single variable at the root. It is in contrast to the past works which usually involve a simultaneous system of multivariate polynomial equations. We checked our algorithm using synthetic as well as real world images.

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